#include #include #include #include #include #include #include namespace DB { namespace ErrorCodes { extern const int NOT_IMPLEMENTED; extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH; extern const int ALTER_OF_COLUMN_IS_FORBIDDEN; } void registerStorageNull(StorageFactory & factory) { factory.registerStorage("Null", [](const StorageFactory::Arguments & args) { if (!args.engine_args.empty()) throw Exception( "Engine " + args.engine_name + " doesn't support any arguments (" + toString(args.engine_args.size()) + " given)", ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH); return StorageNull::create(args.table_id, args.columns, args.constraints); }, { .supports_parallel_insert = true, }); } void StorageNull::checkAlterIsPossible(const AlterCommands & commands, const Context & context) const { auto name_deps = getDependentViewsByColumn(context); for (const auto & command : commands) { if (command.type != AlterCommand::Type::ADD_COLUMN && command.type != AlterCommand::Type::MODIFY_COLUMN && command.type != AlterCommand::Type::DROP_COLUMN && command.type != AlterCommand::Type::COMMENT_COLUMN) throw Exception( "Alter of type '" + alterTypeToString(command.type) + "' is not supported by storage " + getName(), ErrorCodes::NOT_IMPLEMENTED); if (command.type == AlterCommand::DROP_COLUMN) { const auto & deps_mv = name_deps[command.column_name]; if (!deps_mv.empty()) { throw Exception( "Trying to ALTER DROP column " + backQuoteIfNeed(command.column_name) + " which is referenced by materialized view " + toString(deps_mv), ErrorCodes::ALTER_OF_COLUMN_IS_FORBIDDEN); } } } } void StorageNull::alter(const AlterCommands & params, const Context & context, TableLockHolder &) { auto table_id = getStorageID(); StorageInMemoryMetadata new_metadata = getInMemoryMetadata(); params.apply(new_metadata, context); DatabaseCatalog::instance().getDatabase(table_id.database_name)->alterTable(context, table_id, new_metadata); setInMemoryMetadata(new_metadata); } }